diff --git a/test/core/transport/chttp2/decode_huff_fuzzer.cc b/test/core/transport/chttp2/decode_huff_fuzzer.cc
index 93009babae4..6a9d34d2371 100644
--- a/test/core/transport/chttp2/decode_huff_fuzzer.cc
+++ b/test/core/transport/chttp2/decode_huff_fuzzer.cc
@@ -33,7 +33,7 @@ bool leak_check = true;
 absl::optional<std::vector<uint8_t>> DecodeHuffSlow(const uint8_t* begin,
                                                     const uint8_t* end) {
   uint64_t bits = 0;
-  int bits_left = 0;
+  size_t bits_left = 0u;
   std::vector<uint8_t> out;
   while (true) {
     while (begin != end && bits_left < 30) {